In 1950 the Cold War turned hot with the Communist invasion of South Korea. But by November, when Britain's 29th Infantry Brigade landed in Korea, it seemed that the war was all but over. United Nations forces - principally South Koreans and Americans - had decimated the invading North Koreans and were thrusting north towards the Chinese border. Then - catastrophe. China entered the war and panicked UN forces began a 250-mile retreat in sub-zero temperatures. By April 1951, the war hung in the balance.The Chinese had been halted. On the Imjin River, the critical hinge in the line was manned by the British brigade. Then, on the night of 22 April, the largest communist offensive of the Korean War was unleashed. An entire Chinese army assaulted 29th Brigade's scattered strong-points. One by one, the British units were swamped in the 'human waves' of attacking Chinese. For three days hand-to-hand combat raged. At one stage the artillery was firing point-blank, over open sights. Against all odds, 29th Brigade held, but by the third morning it was cut off. The order was given to break out. In a death ride down a valley swarming with enemy, the infantry and tanks battled south. But for one battalion, it was too late. Surrounded on a smoking hilltop, the Glosters fought until their ammunition was exhausted. Of 700 men, less than 50 escaped the trap. The author has interviewed veterans of every unit engaged, to produce an hour-by-hour account of the action as they experienced it in their foxholes. Dramatic, traumatic, moving and inspirational, this is the true story of the band of men who remained at their posts, held an army and astonished the world. Andrew Salmon is a Seoul-based journalist.